In a process of manufacturing a semiconductor, plasma processing for depositing, etching, or the like of a thin film has been widely conducted. In the recent plasma processing, a plasma processing apparatus using a microwave has been often used to make processing gas be in a plasma state.
The plasma processing apparatus using the microwave uses a microwave generator to generate a microwave for plasma excitation. Further, the plasma processing apparatus induces the microwave for plasma excitation into a processing space using a dielectric member which is mounted in the processing chamber to seal the processing space. Further, the plasma processing apparatus supplies the processing gas to the processing space through a through-hole formed in the dielectric member using an injector which is mounted in the dielectric member. The injector and the through-hole of the dielectric member construct a path (hereinafter, appropriately referred to as a ‘gas supplying path’) through which the processing gas is supplied to the processing space. The processing gas supplied from the gas supplying path to the processing space is in a plasma state due to the microwave introduced into the processing space through the dielectric member.
However, in the plasma processing apparatus, the microwave intrudes into the gas supplying path for supplying the processing gas to the processing space to increase electric field intensity, and therefore it is required to suppress the microwave from intruding into the gas supplying path. Japanese Patent Laid-Open Publication No. 2012-238845 discloses that a conductive electric field shielding member is mounted around the injector, which is a portion of the gas supplying path, to shield the microwave from intruding into the gas supplying path using the electric field shielding member.